Nitrate (NO₃⁻) contamination has become a dominant international problem in the aquatic environment, so identifying the sources and transformations of NO₃⁻ is the basis for improving water quality. Since the Jing River is the largest tributary of the Wei River, to understand its water quality, this study collected surface water samples from the Shaanxi section of the Jing River during the dry season. The potential sources of NO₃⁻ were analyzed by hydrochemical and bi-isotopic methods, and the SIAR model was used to estimate the proportional contribution of each source. Results indicated that NO₃⁻-N was the main form of inorganic nitrogen in this area, and the average total nitrogen content was 10.23 mg·L⁻¹, which showed that nitrogen pollution was highly serious; the transformation process of nitrogen in this study area was mainly nitrification; The results of Bayesian model showed that manure and sewage contributed to the most NO₃⁻ (64.39%) in the dry season, followed by soil nitrogen, which was 26.35%. These results help to adopt better nitrogen management measures to meet the national environmental quality standards for surface water.

Biogeochemical and ecological responses to limited external nutrient loading are poorly understood in tropical semi-enclosed coastal lagoons which are highly influenced by hydrological and salinity regimes. With objectives towards ecosystem sustainability via better management of the nutrient inputs, investigations were carried out to estimate the water, salt, and nutrient budget of “Pulicat” hypersaline coastal lagoon for the year 2018–2019. The budget revealed that the annual rate of precipitation and evaporation are the major driving factors regulating the annual residual flow in the lagoon. Limited exchange of water and material had resulted in a hypersaline condition with high spatial and temporal variation in salinity ranging from 20 to 103. In the absence of external loading, nutrient enrichment by internal compensation had resulted in DIN enrichment. DIN constituents are mainly contributed by ammonia, indicative of remineralisation through benthic regeneration. The extended water residence time and enhanced primary production has converted the inner lagoon into a limited phosphate system. The TRIX index also indicates a decline in the trophic status transforming the lagoon from a mesotrophic to a eutrophic system.

The driving pattern of three-wheeled auto-rickshaws is governed by commuter’s demands on certain fixed roads that offer flexible mobility solutions in a mid-size city. This flexibility creates unique driving patterns, frequent stop-and-go conditions, frequent acceleration, braking, and excessive idling, which affect emission rates. Existing emission testing regulation based on the driving cycle does not represent real-world conditions. In this paper, the real-world driving cycle of three-wheeled auto-rickshaw has been developed to provide realistic CO, HC, and NOX pollutants and see the effect of introducing modal shift of electric auto-rickshaw to reduce emission for India. Two policy scenarios were evaluated (1) with a 5% modal shift to electric auto-rickshaw, and (2) without modal shift. The results indicate that with a 5% shift to electric auto-rickshaw, by 2030, emissions will decrease by 6.30% compared to the baseline scenario. Further, by 2030, the projected CO emission would be 1,696,670 ton/year, and HC and NOX emissions would be 2,067,371 ton/year. Results can be useful for policy interventions towards cleaner fuel and the aggressive adoption for reducing pollution from auto-rickshaw.

Non-perennial rivers have attracted significant attention due to the progressive increase in water demand and pollution, river engineering side effects and climate change. The present study investigates the interannual, seasonal and spatial variability of nine water quality variables (pH, colour, turbidity, biochemical oxygen demand, total phosphorus, total inorganic nitrogen, chlorophyll-a, total solids and thermotolerant coliforms) from 93 monitoring river sites distributed over 11 watersheds in the highly populated Brazilian semiarid region. Shapiro–Wilk and Kruskal–Wallis tests were applied for assessing data normality and statistical differences, respectively. Additionally, principal component analysis (PCA) was performed for comparison between temporal and spatial data sets, while the Standardized Precipitation Index (SPI) was used to characterize meteorological drought. The results revealed that spatial variability is more evident than temporal variability. In the temporal scale, the interannual variability is more relevant than the seasonal one. The discharge of wastewater seems to attenuate a seasonal hydrological effect on water quality. There is a deterioration of water quality in most watersheds in the drier years, even in the rainy season. This is especially for colour, total phosphorus, total inorganic nitrogen and thermotolerant coliforms. The abrupt transition from dry to wet years also played an important role in changes in river water quality. This study provides new insights for the understanding of the water quality patterns in non-perennial rivers. In addition, we go on to identify important aspects for the management of these water sources, such as the need for wastewater discharge guidelines within scope of each watershed, and restrictions on the use of soil and water in the driest periods.

The control of low-concentration VOCs in coal-fired flue gas is one of the research hotspots at present. In this work, K₂CO₃ and K₂CO₃-KCl were employed to activate the agricultural wastes (pistachio nut shell) to prepare activated carbon (AC), named PSAC-1 and PSAC-2, respectively. By testing the adsorption performance of the prepared AC and commercial activated carbon (CAC) for the five target VOCs, it was observed that the adsorption capacity of PSAC-2 was the best compared to the other two. Particularly, the adsorption capacity of PSAC-2 (225 mg·g⁻¹) for phenol was 3.8 times that of CAC (59 mg·g⁻¹). In addition, the pseudo-first-order model, pseudo-second-order model, and Elovich model all fitted the adsorption process well, which indicated that both physical adsorption and chemical adsorption existed simultaneously, in which physical adsorption played a dominant role and chemical adsorption played a minor role. Weber-Morris kinetic model was used to illustrate the rate-controlling mechanism; the results confirmed that the stage of external membrane mass transfer was the control stage of adsorption rate. The results of this study can provide some references for the commercial production of biomass-derived AC and the removal of VOCs in coal-fired flue gas.

Recycling mine tailings present a good alternative to manage the waste generated from mining and mineral processing industries. The geopolymer technology provides a green solution to the utilization of mining tailings, avoiding its negative environmental impacts. In this study, we used phosphate mine tailings to produce a novel geopolymeric membrane useful for removing copper ions and humic acid from an aqueous solution. Hydrogen peroxide was used in different concentrations as a porogenic agent, and the membranes exhibited good compressive strength (11.15–43.67 MPa) and high BET surface area (321–384 m² g⁻¹), depending on the amount of hydrogen peroxide used in the synthesis. The hydraulic permeability of the membranes increased from 4.12 × 10⁻⁵ to 11.84 × 10⁻⁵ m s⁻¹ bar⁻¹ when H₂O₂ was added, but the rejection of copper and humic acid remained nearly the same. Copper ions are adsorbed on the membrane surface, while negligible adsorption was measured for humic acid. The geopolymeric membranes efficiently removed Cu²⁺ from water through the combined action of adsorption and rejection by the geopolymer inorganic membrane. The performance of the porous membrane in the removal of copper or humic acid from water increased by factors of 7–19 in comparison to the non-porous membrane.

Carbon dioxide emission and climatic variation have a detrimental influence on the atmosphere as well as on agriculture production. The key aim of the present study was to investigate the influence of carbon dioxide emission on livestock, cereal crops production, rainfall and temperature in China by utilizing the vector autoregressive model and Granger causality test for the period 1988–2017. Variables stationarity was verified by using ADF, P-P and KPSS unit root tests. The outcomes through long-run dynamics exposed that agriculture value added and rainfall have a positive influence on carbon dioxide emission, while cereal crops production, livestock production and temperature have an adverse interaction with carbon dioxide emission. Similarly, the results of the short-run analysis also demonstrate that agriculture value added, cereal crops production, livestock production, rainfall and temperature have a significant influence on carbon dioxide emission with their p-values (0.0488), (0.0885), (0.0263), (0.0096) and (0.5141) respectively. Furthermore, the Granger causality test outcomes also exposed a unidirectional linkage amid the variables. In order to improve agricultural productivity, the Chinese government should take potential steps to minimize the carbon dioxide emission from various industries that trigger climate change.

The anthropogenic/non-sea-salt (nss) inorganic chloride in ambient air was evaluated from the viewpoint of its presence and source attribution by applying the four-stage filter-pack method. Observations were carried out for 1 year by sampling (both particulate matter and gaseous species) on a daily (24 h) basis. The anthropogenic/nss inorganic chloride was detected on 263 days (ca. 72% of the days in 1 year), and concentrations higher than 20 nmol∙m⁻³ were observed on 50 days (ca. 14% of the total sampling days). The source attribution was discussed, taking into account possible sources of in-country volcanic eruption, municipal waste incineration, domestic coal burning, and transboundary transportation. Concentrations of inorganic chloride higher than 20 nmol∙m⁻³ were predominantly observed with a northern wind direction, while high concentrations were infrequent when there was a southern wind direction, strongly suggesting that the in-country volcanic eruption had little influence on the high concentration of nss inorganic chloride. Wind speed had no relationship with concentrations higher than 20 nmol∙m⁻³, indicating that neither municipal waste incineration nor domestic coal burning had much impact on the high concentration. The statistical analyses of the backward trajectory indicated that the transboundary transportation from the area of the northeast and south of China, Mongolia, Russia, and the Sea of Japan contributed greatly to the high concentration of the anthropogenic/nss inorganic chloride along the eastern edge in East Asia.

Triclosan is an antimicrobial agent widely used in personal care products and an emerging contaminant with potential to have harmful effects to edaphic organisms. This study aimed to evaluate the impacts of exposure to triclosan on the microbiota, plants, and edaphic animals using isolated bioassays and a microcosm scale representation (multispecies system). Among the isolated bioassays, the phytotoxicity test with Lactuca sativa, avoidance test with Eisenia andrei, and acute toxicity with E. andrei and Armadillidium vulgare were used. The multispecies system used seeds of L. sativa and Sinapis alba, together with earthworms and terrestrial isopods. This system also evaluated microbial activity through alkaline phosphatase and the metabolic profile using Ecoplate™, BIOLOG microplates. Exposure to triclosan impacted seedling growth in the isolated bioassay and germination and root growth in the microcosm scale assay; it also caused mortality in terrestrial isopods, earthworm avoidance and alteration of alkaline phosphatase, and the consumption profile of carbohydrates and carboxylic acids in the microbiota. The ecotoxicological effects evaluated in the multispecies system were perceived even in low concentrations of triclosan, indicating that the interaction of this xenobiotic with the environment and organisms in a more realistic scenario can compromise ecosystem services.

Evolution of the major kingdoms of life has spanned over the last 4 billion years on Earth. Studies of the process comprise different fields of study with alternative perspectives. This paper focuses on mathematic unification of the subject area; enriching an engineering based structure to advance our understanding of pathways which lead to distinct constructs in life, furthering geographic bordering processes with biological context. Application of logistic regression requires partitioning of variance within cellular and molecular systems; use of higher mathematic technique (multi-objective genetic algorithm) generates variance within the different scales of evolution, the result of which is analogous with the Fisher equation model of gene distribution within populations. Laboratory and field studies were integrated to illustrate emergence in evolutionary processes in the terrestrial/soil environment. Nematological field and laboratory trials validate the existence of triangular relationships within biological communities; further harmonic constants between interacting species may be found with emergent consequence. We distinguish different strategical groupings in the soil community, with the core groupings recognized with Meloidogyne spp. illustrating positive (emergent) growth; Radopholus similis (neutral growth), and Helicotylenchus pseudorobustus (negative growth). The patterns of emergent systems are shown in the extremes of Morocco’s dynamic soil environment. Fuzzy classification methods: Mamdani, Takugi-Sugeno-Kang; additional novel DANCE (Differential Algorithmic Network Centered Emergence) and functional expressions HEAR (Harmonic Evolutionary Algorithmic Resilience), are recommended to give a basis for development of constructs covering different categories of life.